Many sausage products such as wieners and frankfurters comprise cooked meats and are provided with temporary skins or casings during their manufacture and processing. The casings are filled with meat ingredients which are cooked therein. Then, the casings are often removed prior to packaging and sale of the sausages. The casing removal must be accomplished without damaging the sausage shape and texture. It should also preferably be accomplished on a continuous basis and at relative high speed, for economic reasons.
Prior art methods of sausage casing removal have largely relied on the use of compressed air for this purpose. Thus the sausages are conveyed, longitudinally and in single file, as a string joined together by their casings, through a tube in which they are warmed and moistened with steam so as to loosen the casing. Then the casing is slit longitudinally by a knife. A jet of compressed air is then applied to remove the casing. Then the sausage and casing are separated, eg using a suction roller, the casings are discarded and the sausages moved on to a packaging station.
Whilst such a process can be operated efficiently, the use of compressed air is a drawback. Air jets applying the compressed air to the sausages, at sufficient force to effect the casing removal, are extremely noisy, and present the process operator with an unpleasant environment. Earplugs are a necessity for any worker operating in the vicinity of any such process and working apparatus. Moreover, there is a risk of bacterial contamination of the product inherent in the use of air jets, which are liable to pick up airborne bacteria and convey them to the food product.
U.S. Pat. No. 4,222,150 Anderson, describes an apparatus for peeling sausauges in which the sausages, after the casings have been slit, encounter a pair of counter-rotating rollers forming a nip disposed at an obtuse angle to the longitudinal direction of the sausages. One of the roller surfaces may have a roughened portion. the casings are gripped by the nip and passed through it, as they are pulled off the sausages, whilst the peeled sausages pass over the counter-rotating rollers and do not pass through the nip. Whilst the Anderson apparatus avoids the use of air jets, it requires the use of liquid jets to keep the rollers clean and properly operational. It is inefficient in practice, and liable to cause damage to the sausages as they contact the peeling rollers.
It is an object of the present invention to provide a novel sausage casing removal apparatus, but nevertheless operates efficiently over extended periods of time.
It is a further object of the invention to provide such an apparatus which avoids the necessity of using compressed air.